Old 02-01-2013, 05:51 PM
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Sensor Light Loss with Fast Lenses

Thinking of buying a fast lens? F1.2 say.Then please read this


It depends what pixel size your camera has, bigger is better.

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Old 02-01-2013, 11:58 PM
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Very interesting Bert! It's sad to see that the open letter was from 2010 and no response has come from any of the camera manufacturers.
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Old 04-01-2013, 07:12 AM
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Sensor pixels are sensitive to the angle of light striking them. They usually are setup to only receive light within 15 degrees off vertical. The microlenses are designed to "straighten up the light".

This probably accounts for the drop off in performance with faster F ratio.

It can be an important factor. The Sony Nex 7 has an engineering fault where an ultra wide lens causes colour shift to magenta because of the above.

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Old 04-01-2013, 04:16 PM
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thanks for the post Bert. Often wondered how the chip manufacturers arranged microlenses to accept wide light cones - looks like the simple answer is that they don't.

no chip manufacturers seem to publish detailed data on cross-talk either and that might well be another problem with the slightly crazy race to tiny pixels (and maybe this effect will also be worse with fast optics).

Last edited by Shiraz; 05-01-2013 at 11:33 AM.
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